What If the U.S. Air Force Gave the Mach 3 SR-71 Missiles? Meet the YF-12

Summary and Key Points: The Lockheed A-12 Oxcart was the precursor to the SR-71 Blackbird and was developed for high-altitude reconnaissance. A fighter-interceptor variant, the YF-12, was designed to replace the F-106 Delta Dart. The YF-12 featured a second cockpit for a fire control officer and could carry AIM-47 Falcon air-to-air missiles.

-It set speed and altitude records but was canceled due to the rising costs of the Vietnam War and the emergence of ICBMs.

-Only three YF-12s were built...